fix: avoid creating unnecessary memory blocks

[TomAFrench]

Description

Problem*

Resolves #7113

Summary*

This is a starting point for the issue #7113.

Additional Context

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [For Experimental Features] Documentation to be submitted in a separate PR.

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[github-actions]

Execution Report

Program	Execution Time	%
sha256_regression	0.052s	0%
regression_4709	0.001s	0%
ram_blowup_regression	0.602s	-6%
rollup-root	0.105s	0%
rollup-merge	0.007s	0%
rollup-block-root	37.900s	-2%
rollup-block-merge	0.104s	-2%
rollup-base-public	1.226s	0%
rollup-base-private	0.455s	0%
private-kernel-tail	0.019s	0%
private-kernel-reset	0.313s	0%
private-kernel-inner	0.068s	0%

[github-actions]

Compilation Report

Program	Compilation Time	%
sha256_regression	1.020s	-3%
regression_4709	0.797s	2%
ram_blowup_regression	16.200s	-2%
rollup-root	3.522s	-5%
rollup-merge	2.140s	1%
rollup-block-root-single-tx	142.000s	-1%
rollup-block-root-empty	2.120s	-6%
rollup-block-root	156.000s	5%
rollup-block-merge	3.514s	-6%
rollup-base-public	28.520s	-1%
rollup-base-private	10.038s	-4%
private-kernel-tail	0.940s	-3%
private-kernel-reset	6.134s	0%
private-kernel-inner	2.028s	0%

[github-actions]

Execution Memory Report

Program	Peak Memory
keccak256	74.630
workspace	123.830
regression_4709	315.940
ram_blowup_regression	512.570
rollup-root	498.700
rollup-merge	473.340
rollup-block-root	1230.000
rollup-block-merge	498.710
rollup-base-public	734.390
rollup-base-private	590.810
private-kernel-tail	180.840
private-kernel-reset	245.440
private-kernel-inner	208.850

[github-actions]

Compilation Memory Report

Program	Peak Memory
keccak256	77.560
workspace	123.400
regression_4709	424.070
ram_blowup_regression	1460.000
rollup-root	601.600
rollup-merge	494.440
rollup-block-root-single-tx	16060.000
rollup-block-root-empty	489.060
rollup-block-root	16070.000
rollup-block-merge	601.590
rollup-base-public	2380.000
rollup-base-private	1140.000
private-kernel-tail	207.350
private-kernel-reset	584.400
private-kernel-inner	294.600